Validation of Lung Cancer Screening Value during COVID-19 Pandemic

Purpose: The COVID-19 pandemic has greatly affected outpatient screening programs. Diagnoses of lung cancer, the leading cause of cancer death in the United States, were decreased during the pandemic. Low dose CT (LDCT) is the cornerstone of lung cancer screening in at-risk patients, with test sensitivity and specificity of 85% and 99%, respectively. LDCT enables early detection and treatment before disease progression. The lung imaging reporting and data system (Lung-RADS) provides a standardized template for characterizing lung nodules and stratifying their risk of malignancy. Lung cancer screening studies in the periods before, during, and after the peak of the pandemic are analyzed to determine incidence of suspicious pulmonary nodules with variable screening rates.

Methods/Materials: This is a retrospective cohort analysis of patients receiving lung cancer screening LDCT examinations at our Staten Island, New York based outpatient imaging center. Time periods were divided by the pre-pandemic (1/2019-2/2020), COVID-19 peak (3/2020-7/2020), and post-pandemic peak (8/2020-5/2021). Monthly screening volume was analyzed, alongside patient age, sex, and Lung-RADS pulmonary nodule classification. Incidence of suspicious (4A) and very suspicious (4B) nodules were compared in these time periods.

Results: Average monthly lung cancer screening CT examinations decreased from pre-pandemic to peak-pandemic levels (29.6 vs 24.8 exams per month) and increased in post-peak period (59.3 exams per month). The incidence of high-grade pulmonary nodules (Lung-RADS 4B) were demonstrated to be higher in the post-peak vs. the pre-pandemic periods (2.6% vs. 1.0% incidence).

Conclusions: During the peak pandemic period, overall lung cancer screening volume decreased. After the peak pandemic, the number of lung cancer screening examinations appreciably increased. There was an increased incidence of very suspicious pulmonary nodules. These findings support LDCT lung cancer screening exams as a core component of lung cancer detection and management. Further efforts should be devoted to expanding lung cancer screening programs, along with an increased commitment of resources to ensure that patients are regularly screened.